Metal punch stamp: suitable for stamping aluminium, brass, copper, silver, gold and ect. (also fits for annealed steel and hot stamping on steel) If you need to customize the stamp, please send me high-resolution black and white (not grayscale and not colourful) logo in JPEG, PNG, AI, EPS, CDR, JDP or PDF format. The optional size of the stamp is 4-20mm. If you want it larger than 20mm, it needs to be custom made. The image should be sent before the purchase to make sure it is doable. Black areas of your logo will be raised on a stamp (black areas of Your logo will be pressed into the blank).